Can I bolt a 4 speed transmission to a 3 speed belhousing?

yes i did it 30yrs ago in a 64 cuda you have to weld the bellhousing to and a plate for the bolt patern

yes i did it 30yrs ago in a 64 cuda you have to weld the bellhousing to add a plate for the bolt patern change from 3-4 speed

Only with an adapter or having the 3 speed housing re-machined. On many 70's mopars some 3 speed cars came with the 4 speed bellhousing as it is machined with both 3 and 4 speed patterns....

In a quick bolt up, you might not, but check to make sure you don't have an extra set of threaded bolt holes in your bellhousing....

-D.Idiot